Electric coffee-roaster.



No. 718,135 PATENTED JAN. 13, 1903. G. C. LESTER.

ELECTRIC COFFEE ROASTER.

- APPLICATION IIi-BD MAR. 8, 1902.

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No. 718,135. PATENTED JAN. is, 1903.

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ELECTRIC GOPFEE ROASTER. APPLICATION mum HA3. 8, 1902.

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No. 718,135. PATENTED JAN. 13, 1903 G. G. LESTER.

ELECTRIC COFFEE ROASTER.

APPLICATION FILED MAR. B, 1902.

I0 IODEL.

UNTTnn STATES PATENT OFFICE.

GEORGE O. LESTER, OF NEW YORK, N. Y.

ELECTRIC COFFEE-ROASTER.

IZPECIFIGATION forming part of Letters Patent No. 718,135, dated January13, 1903.

Application filed March 8, 1902. Serial No. 97,381. (No model.)

To aZZ whom it may concern:

Be it known that I, GEORGE O. LESTER, a citizen of the United States,residing at New York, in the county of New York and State of New York,have invented new and useful Improvements in Electric Coffee-Roasters,of which the following is a specification.

My invention relates to electric coffee-roasters, the object of the samebeing to provide novel means whereby electric heaters may be employed inconnection with a rotary drum or receptacle containing the coffee, sothat contact between the coffee and said heaters is avoided.

A further object of the invention is to provide novel means for applyingelectric heaters in connection with a rotary coffee-containing drum orreceptacle, which avoids the necessity for passing the noxious fumes ofcombustible fuel therethrough.

A further object of the invention is to provide novel means forconnecting up the various heaters in the electric circuit from thegenerator, whereby one or more of the same may be cut in or out of thecircuit for regulating the degree or intensity of the heat applied.

Other objects and advantages of the invention will hereinafter appear,and the novel features thereof will be set forth in the claims.

In the drawings forming part of this specification, Figure 1 is an endView of an electric coffee-roaster constructed in accordance withmyinvention. Fig. 2 is a top plan View of the same. Fig. 3 is a verticallongitudinal section on the line 3 3 of Fig. 2. Fig. 4 is a verticaltransverse section on the line 4 4 of Fig. 2. Fig. 5 is an end view ofone of the heads of the rotary drum. Fig. 6 is a detail sectional viewof the same. Fig. 7 is a view showing, partly in section and partly inelevation, a set of three heaters. Fig. 8 is a detail cross-sectionalView of one of the heaters, and Fig. 9 is a diagrammatic view showingthe circuit connections.

Like reference-numerals indicate like parts in the difierent views.

The main frame of the machine may be of any suitable form andconstruction. Mounted therein is a rotary drum or receptacle 1, in whichthe coffee is roasted, the same being adjustably secured to a horizontalshaft 2,

having suitable bearings in the main frame and provided with a gear 3 onone end. The gear 3 meshes with the pinion 4 on a countershaft 5,carrying a bevel-gear 6, which meshes with a pinion 7 on thearmature-shaft S of an electric motor 9. The said motor 9 and theconnections between the same and the gear 3 are suitably supported onthe main frame of the machine. The drum 1 has a cylindrical metallicwall 10 and a circular metallic head 11 at one end, these two partsbeing connect ed to each other, as clearly shown. The end of said drumopposite the head 11 is open, but is normally covered bya face-plate 12,secured to or forming part of the main frame. The upper end of theface-plate 12 has an opening 13 therein, communicating with the interiorof the drum 1 and having leading thereinto a hopper 14 for supplyingcoffee to the machine. The opening 13 is adapted to be closed when thedevice is in operation by a sliding gate or valve 15. Adjacent to thelower end of the face-plate 12 the same is provided with adischarge-opening 16, by means of which the coffee after it has beenroasted may be removed from the machine, the said opening being normallyclosed while the device is in operation by a hinged gate or door 17. Anopening in the face-plate 12, closed by the flap or valve 18, may alsobe provided for sampling the coffee under treatment. Beneath thedischarge-opening 16 I prefer to employ a car 19 for receiving thecoffee from the drum 1 and for the convenient delivery of the same toany suitable point. This car is provided with a foraminous bottom 20,having a passage 21 beneath the same, provided with a spout or nozzle22, by means of which the same may be connected with a suctionfan orother exhausting device for drawing air through the mass of coffee onthe bottom 20, and thereby facilitating the cooling of the same.

The open end of the drum 1 is braced and supported by means of a spider23, the arms of which are connected at their inner ends to a hub orsleeve 24, embracing and adjustably secured to the shaft 2, and theouter ends of which are secured to a ring 25, parallel to the head 11 ofthe drum and secured to the cylindrical wall thereof. The head 11 andthe cylindrical wall 10 of the drum 1 are both covered by a layer 26 ofasbestos or other like heat-non-conducting material, and said layer ofasbestos is itself covered by a cylindrical copper or other metallicsheet 27, extending around the cylindrical wall 10, and a circularcopper or other metallic disk 28 outside the head 11. The copper sheet27 and disk 28 are provided for the purpose of protecting the layer 26of asbestos which surrounds the body of the drum and for the purpose ofimproving the appearance of the device as a whole.

Located within the drum 1, parallel to the cylindrical wall thereof, isa foraminous diaphragm or partition 29, the same being constructed ofperforated sheet metal, wirenetting, or other like material. Thispartition is secured at one end to the head 11 of the drum 1 and at theother end to an annular lip or flange 30 on the ring 25. The same formswithin the drum 1 a central cylindrical receptacle 31, in which thecoffee is roasted, and a surrounding annular chamber 32, in which theelectric heaters are located and from which the heat is transmittedthrough the foraminous diaphragm 29 to the coffee within the receptacle31. Located within the receptacle 31 are the spiral flights or ribs 3334, designed for the purpose of agitating and keeping in movement fromend to end of the receptacle the coffee contained therein. The outeredge of the spiral flight or rib 33 lies in contact with the innersurface of the foraminous diaphragm 29, whereas the outer edge of theflight or rib 34 is removed from the inner surface of the foraminousdiaphragm 29 bya distance equal to the width of the flight 33. A passageis thereby produced outside the flight 34, between itand the diaphragm29.

To provide closed joints between the rotary drum 1 and the fixedface-plate 1.2 and prevent any of the coffee beans or berries in thereceptacle 31 from escaping from the machine or from gaining access tothe bearing parts, I provide on the inner surface of the face-plate 12two annular ribs or bearingsurfaces 35 36 and form on the outer surfaceof the ring 25 two outwardly-projecting annular ribs or bearing-surfaces37 38, which cooperate with the annular ribs 35 and 36. The parts beingadjusted so that these ribs lie in close contact with each other, theescape of the coffee-berries from the receptacle 31 in which they arecontained is rendered impossible. If, however, from wear or from anyother cause the ribs 35 and 37 and 36 and 38 should become loose orseparated from each other, they may be readily tightened by the meansnow to be described.

The outer end of the shaft 2 is provided with screw-threads 39, uponwhich fits a nut 40, abutting against the bearing 41 of said shaft. Thisnut has extending through it, so as to engage the threads 39 on theshaft 2, a looking or set screw 42. By loosening the set-screw 42 thenut 41 may be turned so as to draw the shaft 2outwardly and move withsaid shaft the drum 1, so as to bring the ribs 37 and 38 on the ring 25into close contact with the ribs 35 and 36 on the face-plate 12. Whenthe proper movement of the shaft 2 and the parts connected therewith hasbeen effected, the set screw 42 is screwed inwardly into engagement withthe threads 39 and the further movement of the nut in either directlonis prevented. The parts will thereby be locked in position withoutdanger of accidental separation.

As heretofore stated, the electric heaters are located within theannular chamber 32, surrounding the foraminous diaphragm 29. Thischamber, it will be noted, is completely closed 011 all sides exceptthat covered by the diaphragm 29, so that the air heated therein mustnecessarily pass therefrom through the openings in the diaphragm 29 tothe interior of the receptacle 31, in which the cofiee is roasted. Theseheaters are arranged in sets at various points around in the chamber 32,the members of each set being designated by the reference-numerals 43 4445. Four sets of heaters have been illustrated and three heaters havebeen shown in each set; but it is obvious that the number of sets may bevaried and the number of heaters in each set may be increased ordecreased. Each of said heaters consists of a hollow cylindrical spool46, having a spiral groove 47 on its outer surface, around which theheating-coil 48 is passed and in which said coil is seated. Each of saidspools has a metallic core or stifiening-rod 49, extendingtherethrough,.

and is provided with rectangular heads 50. The said heads 50 arerabbeted, as shown at 51 to provide overlapping lips or flanges 52. Whenthe heaters are assembled within the annular chamber 32, the same aresupported upon recessed blocks or standards 53, secured to base-plates54, attached to the inner cylindrical wall 10 of the drum 1. The saidheaters are heldin placeupon the blocks or standards 53 by means ofscrews or pins 55, which extend through the spools 46, as

clearly shown in Fig. 8 of the drawings.

When in place, the flanges 52 on the heads 50 of the adjacent heatersoverlap each other, and the same are thereby secured in place withoutdanger of accidental derangement. The metallic core 49 in each of thespools 46 serves to stiffen and strengthen said spools, and in the eventof the breakage of the porcelain of which said spools are made serve toprevent the broken parts thereof from falling away. The heating-coilsare thereby prevented from falling down and short-circuiting through theother coils.

To provide means for supplying current to the various heaters arrangedin the annular chamber 32, I arrange upon the outside of the metallicdisk 28, which covers the sheet 26 of asbestos on the outside of thehead 11 of the drum 1, a series of contact-rings 56 57 58 59. Thesecontact-rings are mounted upon an annular band 60 of insulatingmaterial, se-

cured to the disk 28. Cooperating respectively with the contact-rings 5657 58 59 are the brushes 61 62 63 64, carried by a hanger arm or support65. The heater 43 of each set of heaters is connected through the wire66 with the outer ring 56. The heater 44 of each set of heaters isconnected through the wire 67 with the contact-ring 57. The heater 45 ofeach set of heaters is connected through the wire 68 with thecontact-ring 58, and all of the heaters of each set are connectedthrough the wire 69 with the contact-ring 59. It will thus be seen thatthe heaters 43 of each set are connected up in multiple, as well as theheaters 44 of each set and the heaters 45 of each set. Coiiperating withthese parts is a switchboard or controller comprising a pivotedswitch-arm 70, having a segmental contact-strip or bridge-piece 71thereon, and the contacts 72 73 74, designed to be engaged by the strip71. Stops 75 76 limit the swinging movement of the switch-arm 70inopposite directions. The contact 72 is connected through the wire 77with the brush 61. The contact 73 is connected through the wire 78 withthe brush 62, and the contact 74 is connected through the wire 79 withthe brush 63. The brush 64 is connected through the wire 80 with thecommon return-wire 81 of the sys tem. The switch arm or lever 70 isconnected with the generator 82 or other source of electrical supply byway of the wires 83, 84, and 85, the wires 84 and 85 having interposedbetween them an ordinary switch or cut-out 86. The motor 9 is suppliedfrom the generator 82 through the wires 87, 88, and 89, the wire 89being connected with the general return-wire 81. Between the wires 87and 88 is interposed an ordinary switch or cut-out 90. In thereturn-wire 81 is interposed an ordinary switch or cut-out 91.

By the construction just described it will be seen that the motor 9 andthe heaters are supplied from a common source of electrical energy. Theconnections between the generator 82 and both the motor and heaters maybe cut on or off by the switch 91. The supply to the heaters through theswitch-arm 70 may be cut on or off independently of that to the motor 9by means of the switch 86, and the supply to the motor 9 may be cut onor off independently of that to the heaters through the switch-arm 70 bymeans of the switch 90. \Vhen a high degree of heat is desired in theroaster, all of the heaters 43, 44, and 45 of each set will be throwninto operation. This may be effected by moving the switch-arm 70 to itsextreme position to the right, in which case the contact-strip 70 willbe brought into engagement with all of the contacts 72, 73, and 74. Theflow of current from the generator will then be over the following path:wires 83 and 84, switch 86, wire 85, switch-arm 70, contact-strip 71,contacts 72, 73, and 74, wires 77, 78, and 79, brushes 61, 62, and 63,contact-rings 56, 57, and 58, wires 66, 67, and 68 of each set ofheaters, heaters 43, 44, and 45 of each set, wires 69 of each set ofheaters, contact-ring 59, brush 64, wires 80 and 81, and switch 91. Itwill thus be seen that current is supplied to each of the heaters ofeach set and that the highest degree of heat which the heaters arecapable of supplying will be generated. If a lower degree of heat bedesired, the switch-arm 70 will be moved to the left, so as todisconnect the contact-strip 71 from the contact 74. The wire 79, brush63, contactring 58, wire 68 of each set of heaters, and the heater 45 ofeach set will be thrown out of the circuit above traced, and the heaters43 and 44 of each set of heaters will alone be in operation. If a stilllower degree of heat be desired, the switch-arm 70 will be moved stillfarther to the left, disconnecting the contact-strip 71 from thecontacts 73 and 74. Said contact-strip 71 will then be in engagementwith the contact 72 alone, as illustrated in Fig. 9 of the drawings. Thecircuit through the apparatus will then be as follows: Generator 82,wires 83 and 84, switch 86, wire 85, switch-arm 70, contact-strip 71,contact 72, Wire 77, brush 61, contact-ring 56, wire 66 of each set ofheaters, heater 43 of each set, wire 69 of each set of heaters,contact-ring 59, brush 64, wires 80 and 81, and switch 91, back to thegenerator. It will thus be seen thata single heater 43 of each set ofheaters is now in operation. By a simple manipulation of the switch-armor lever 70, therefore, one or more of the heaters of each set may becut into or out of the circuit and the heat generated within the roasterthereby increased or decreased.

In the operation of my roaster the sliding gate or valve 15 is opened,and coffee is introduced to the interior of the receptacle 31 throughthe hopper l4 and the opening 13 in the-face plate 12. When asufficientquantity of coffee has been thus introduced into the machine,the gate orvalve 15 is closed,and the current is turned on to the motor 9 and oneor more of the heaters. This is effected by closing the switch 90between the wires '87 and 88, leading to the motor and by moving theswitch-arm 70 so as to bring about the engagement of the contact-strip71 with one or more of the contacts 72, 73, and 74. When the motor 9 isenergized, the armature-shaft 8 thereof is rotated, and the motion ofsaid shaft is transmitted through the gearing described. to the shaft 2,to which the drum 1 is secured. The said drum is thereby rotated and thecoffee within the receptacle 31 is kept in motion and has a longitudinalmotion imparted to it by the spiral flights or ribs 33 and 34. At thesame time one or more of the heaters 43, 44, and 45 of each set isthrown into operation, and the air within the annular chamber 32 israised to the requisite degree of heat for roasting. This air passesfrom the chamber 32 into the receptacle 31 through the foraminousdiaphragm 29 and acts upon the coffee contained within said receptacleto roast or parch the same. As the heaters 43, 44, and 45 are located inthe chamber 32, which is separate from the receptacle 31, in which thecoffee itself in located, it will be observed that there can be nodirect contact between the coffee-beans and the heaters, which wouldserve to spot or unequally heat the same. This is an objection to priorapparatus which my invention overcomes. Furthermore,as the coffeeisroasted by means other than the cumbustion of suitable fuel, there areno noxious gases to come in contact with the coffee-bean, and therebydeteriorate or contaminate the flavor or aroma thereof. Furthermore, asthe coffee is roasted in a chamber which is closed on all sides there isno opportunity for the escape of vapors or aroma from the coffee, whichare in other forms of apparatus with which I am familiar allowed to goto waste. In other words, all the vapors, flavors, and aromas which arecontained in the original green coffee-bean are retained in the sameafter the coffee has been roasted. No artificial moistening of theroasted bean is necessary, as none of the original moisture containedtherein is driven off. At such times as may be desired the coffee undertreatment may be tested by withdrawing a portion of the same containedin the re-' ceptacle 31 through the opening in the faceplate 12, whichis closed by the cap or cover 18. After the bean has been subjected tothe roasting action of the heaters 43, 4:45, and 4:5 for a suitableperiod the gate or door 17 on the face-plate 12 is opened and thecontents of the receptacle 31 are discharged through the opening in saidface-plate into the caror receptacle 19. In this car the coffee may besuitably cooled by suction applied to the nozzle 2:2 and the sameconveyed to any suitable point.

Having now described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. In a coffee-roaster, a rotary drum having a receptacle therein inwhich the coffee is roasted, a separate chamber outside said receptaclebut communicating therewith, and an electric heater carried by said drumand located in said chamber.

2. In a coffee-roaster, a rotary drum having a foraminous diaphragmtherein dividing the same up into a receptacle in which the coffee isroasted and a separate chamber, and electric heaters mounted in saidchamber.

3. In a coffee-roaster, a rotary cylindrical drum having a cylindricalforaminous diaphragm therein dividing the same up into a receptacle inwhich the coffee is roasted and an annular chamber surrounding saidreceptacle, and electric heaters carried by said drum and located insaid chamber.

4. In a coffee-roaster, a rotary cylindrical drum having a cylindricalforaminous diaphragm therein dividing the same up into a receptacle inwhich the coffee is roasted and an annular chamber surrounding saidreceptacle, electric heaters carried by said drum and located withinsaid chamber, and spirally-arranged ribs or flights within saidreceptacle.

5. In a coffee-roaster, a rotary cylindrical drum having a cylindricalforaminous diaphragm therein dividing the same up into a receptacle inwhich the coffee is roasted and an annular chamber surrounding saidreceptacle, electric heaters carried by said drum and located withinsaid chamber, and a plurality of spirally arranged oppositely extendingflights or ribs located within said receptacle,

-one of said flights or ribs having its outer edge in contact with saiddiaphragm, and the other located within the first and a short distancefrom the inner surface of said diaphragm.

6. In a coffee-roaster, a rotary drum having one end open and the otherend closed, and having an imperforate cylindrical wall, a cylindricalforaminous diaphragm,dividingsaid drum into a receptacle in which thecoffee is roasted, and an annular chamber surrounding the same, electricheaters carried by said drum and located within said chamber, a fixedface-plate opposite the open end of said drum having an opening thereincommunicating with said receptacle, a hopper leading to said opening,and a gate or valve controlling the passage through said opening.

7. In acoffee-roaster, a rotary shaft, a drum secured thereto andcomprising a cylindrical imperforate peripheral wall, an imperforatedisk secured thereto and constituting one head, a ring connected to theopposite end of said cylindrical wall, a spider connecting said ringwith said shaft, and a cylindrical foraminous diaphragm dividing saiddrum into a receptacle in which the coffee is roasted, and an annularchamber surrounding the same, electric heaters carried by said drum andlocated in said chamber, a fixed face-plate opposite the open end ofsaid drum having an opening therein communicating with said receptacle,a hopper leading to said opening, and a gate or valve controlling thepassage through said opening.

8. In a coffee-roaster, a rotary shaft, a drum secured thereto, rotatedthereby and having one end open, a cylindrical foraminous diaphragmdividing said drum into a receptacle in which the coffee is roasted, andinto an annular chamber surrounding the same, electric heaters carriedby said drum and located in said chamber, a fixed face-plate oppositethe open end of said drum having an opening therein communicating withsaid receptacle and through which the coffee to be roasted is deliveredto said receptacle, means for closing said opening, annular bearing-ribson the inner surface of said face-plate, similar bearing-ribscooperating therewith on the adjacent face of said drum, and means foradjusting said drum longitudinally to bring about close, contact betweensaid bearing-ribs.

9. Inacoffee-roaster, arotar shaft, adrum secured thereto, rotated therey and having one end open, a cylindrical foraminous diaphragm dividingsaid drum into a receptacle in which the coffee is roasted, and into anannular chamber surrounding the same, electric heaters carried by saiddrum and located in said chamber, a fixed face-plate opposite the openend of said drum having an opening therein communicating with saidreceptacle and through which the coffee to be roasted is delivered tosaid receptacle, means for closing said opening, annular bearing-ribs onthe inner surface of said plate, similar bearingribs cooperatingtherewith on the adjacent face of said drum, a nutbn the screw-thread edend of said rotary shaft adapted to engage one of the hearings in whichsaid shaft is mounted, for moving said shaft and the drum carriedthereby longitudinally, and means for locking said nut to said shaft.

10. Inacoffee-roaster,the combination with a rotary drum having areceptacle therein in which the coffee is roasted and having an annularchamber surrounding said receptacle, of a plurality of sets of electricheaters located within said chamber, posts or uprights secured to theinner surface of the cylindrical Wall of said drum, having recesses attheir inner ends in which said heaters are seated, each of said heaterscomprising a hollow spool of insulating material having an externalspirally-arranged groove therein,and having rectangular heads rabbetedto form overlapping tongues, a stiffening rod or bar extending througheach of said spools, and securing devices extending through said spoolsinto said posts, the tongues on the heads of said spools overlappingthose on the adjacent heads.

11. Inacoifee-roaster,thecombination with a rotary drum having anannular chamber therein surrounding the coffee-receptacle,and aplurality of sets of electric heaters carried by said drum and arrangedat intervals in said chamber, and means for cutting one or more of theheaters of each set into or out of circuit.

12. In acoffee-roaster,the combination with a drum having an annularchamber therein surrounding the receptacle in which the coffee isroasted and, an electric motor for rotating said drum, of a source ofelectrical energy,

means for cutting said motor into or out of circuit, a plurality of setsof electric heaters carried by said drum and arranged at intervals insaid chamber, and means for cutting one or more of the heaters of eachset into or out of circuit independently of said motor.

13. In a coifee-roaster,the combination with a rotary drum and aplurality of sets of electric heaters carried thereby, of a plurality ofcontact-rings carried by but insulated from said drum, an electricgenerator, a plurality of contact brushes bearing respectively againstsaid rings, one of which brushes is connected with the return-wire ofsaid generator, a circuit-controller comprising a plurality of contactsconnected respectively with the other of said brushes, a switch-armconnected with the other pole of said generator and having acontact-stri p thereon adapted to engage said contacts, separateelectrical connections between each of the contact-rings Which areengaged by the brushes connected with said contacts, and each of theheaters of the different sets, and a return connection between each setof heaters and the contact-ring which is engaged by the brush connectedwith the common return of said generator.

In testimony whereof I have hereunto set my hand in presence of twosubscribing witnesses.

GEORGE O. LESTER.

Witnesses:

WM. M. STOOKBRIDGE, GEO. W. REA.

